Device for mixing viscous materials



Oct. 30, 1956 E. MINEAH 2,763,405

DEVICE FOR MIXING vxsceus Mam-MUS Filed May 15. 1953 Sheets-Shea 1.

52 INVENTOR,

Ana/251x 05 E M/NEAH sa BY I ATTORNEY Oct. 30, 1956 v 1. .,1-2. MINEAH DEVICE FOR MiX'mc-vIscoUs MATERIALS FiledMay 15, 1953 V 4 Sheets-Sheet 2 lNVENTOR LAWRENCE E M/NEAH ATTORNEY Oct. 30, 1956 E. MlNEAH 2,768,405

DEVICE FOR MIXINY; vIScus MATERIALS Filed May I5,- 1953 4 Sheets-Sheet 4 \Wll/I/Il/I/ INVENTOR,

LAu/QEN E E M/NEAH BY I ATTORNEY United States Patent DEVICE FOR MIXING VISCOUS MATERIALS Lawrence E. Mineah, La Mesa, Calif., assignor to Coast Paint and Chemical Co., Los Angeles, Calif., a corporation of California Application May 19%, Serial No. 35Eg220 17 Claims. (Cl. 18-2) This invention relates to a device for mixing viscous materials, such as rubber-like sealing compounds.

Such sealing compounds may be applied, for example, upon engaging edges of surfaces, such as around the flange of a cover plate for airplane gasoline tanks, between bolts and nuts, and the like. The compounds, usually rubber-like and tacky, harden after continued exposure to air.

The individual constituents are a synthetic rubber-like material and a catalyzer. When mixed, setting or hardening takes place at a rate proportional to the temperature of the mixture.

In order etficiently to utilize such compounds, they should be mixed at the time they are to be applied or shortly in advance of such time, and the mixture should be maintained as cool as possible. Otherwise, the setting of the material would render it incapable of use.

It is one of the objects of this invention to provide a compact, portable and inexpensive mixer and applicator that efficiently perform the functions of mixing viscous material of this character, and that may conveniently be held and controlled by the hand of the user.

It is another object of this invention to provide -a mixer of this character that accurately controls the proportion of the constituent materials of the final mixture. For this purpose, gear pumps are provided that-urge the constituents to a mixing chamber. The gear pumps are driven by a common shaft, and thus the positive displacement of the gear pumps ensures a definite proportion of the constituent materials independent of the rate that the gear pumps are driven.

It is another object of this invention to provide an improved manner of urging constituent materials into a mixing apparatus by the application of air pressure.

It is still another object of this invention to provide novel means for cooling the mixing apparatus. For this purpose, an air motor is used for operating the device, and the exhaust of the air motor is utilized for cooling effects.

It is still another object of this invention to make it possible quickly and easily to supply the apparatus with the constituent materials to be mixed.

it is still another object of this invention to provide a device of this character that can be easily cleaned.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several embodiments of the invention. For this purpose, there are shown a few forms in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figures 1 and 2 are respectively front and side elevations of a device incorporating the present invention;

ice

Figure 3 is an enlarged vertical fragmentary sectional view, taken along a plane indicated by line 3-3 of Fig. 1;

Fig. 4 is an enlarged vertical fragmentary sectional view, taken along a plane indicated by line 4-4 of Fig. 2;

Fig. 5 is an enlarged fragmentary sectional view, taken along a plane indicated by line 5-5 of Fig. 3, a portion of the apparatus being broken away;

Fig. 6 is an enlarged fragmentary sectional view, taken along a plane indicated by line 6-6 of Fig. 5;

Figs. 7 and 8 are enlarged fragmentary sectional views, taken along planes indicated by lines 7-7 and 88 of Fig. 4, and showing, respectively, the manner in which pressurized air enters the casing and the manner in which the materials to be mixed may be inserted;

Fig. 9 is a plan view of an apparatus incorporating a modified form of the present invention;

Fig. 10 is an enlarged sectional view, taken along a plane indicated by line 10-10 of Fig. 9;

Fig. 11 is an enlarged sectional view, taken along a plane indicated by line 11-11 of Fig. 9; and

Fig. 12 is a sectional view, taken along a plane indicated by line 1212 of Fig. 10.

The device, as shown in Figs. 1 and 2, includes a casing formed by two generally hemispherical parts 11 and 12 are are aligned and opposed to each other.

The two constituent materials (such as a catalyst and a rubber-like synthetic material) are placed, respectively, in collapsible bags or containers formed by flexible walls '13 and 14 (Figs. 3 and 5) accommodated within the hemispherical casing structures 11 and 12. These walls are preferably made of thin rubber. The materials in the containers formed by walls 13 and 14 are utimately mixed and discharged through a spout structure 15. The intermingling of the materials prior to discharge is effected in a manner to be hereinafter described.

A body structure 16 (Figs. 2, 3, 4, 6, 7 and 8) serves as a means for mounting and supporting the casing structures 11 and 12 and the walls 13 and 14. The body 16 may conveniently be formed of symmetrical halves 16a, 16b held together by bolts 160. The body 16 has symmetrically disposed annular flanges 17 and 18 (Fig. 3) forming recesses 19 and 20.

The walls 13 and 14, which are generally of hemispherical configuration, cooperate with the recesses 19 and 20 of the body 16 to form chambers 21 and 22. The circular edges of the Walls 13 and 14 are clamped to the body structure 16 by being pressed against the walls of the recess 19 and 20 by the aid of rings 23 and 24.

The housing members 11 and 12 are threadedly acco modated on the exterior of the flanges 17 and 18. These casing members 11 and 12 form pressure chambers surrounding the walls 13 and 14. By the application of air pressure to the interior of the casing members 11 and 12, the materials contained in the chambers 21 and 22 are urged toward the body 16 and through various passageways, outwardly into the spout 15.

The materials from the chambers 21 and 22, respectively, pass upwardly of the body 16 through converging ports or passages 25 and 26 of the body (Figs. 3 and 5). The body has a central recess 27 extending above these passages.

A mixing chamber 30 receives the materials from the passages or ports 25 and 26. The chamber 38 is formed by a through axial aperture 29 of a fitting 28, threadedly accommodated in the body recess 27, and the central portion of the bottom surface of the body recess 27. For this purpose, the fitting 28 has an annular depending fian e engaging the bottom surface of the body recess 27 about the upper openings of the passages or ports 25 and 26.

A rotatable chopper 32 in the mixing chamber 30 causes intimate intermixture of the constituent materials 3 passing therethrough. The material mixed by the chopper 32 is conducted to the spout by the aid of a plug 33 threadedly received in the top of the through aperture 29 of the fitting 23. Thisrplug 33 has an appropriate passage 34 communicating, respectively, with the chamber 30 and the spout 15.

Rotary gear pump structures are provided for urging the material from the chambers 21 and 22 upwardly through the passages 25 and 26 to the mixing chamber 30.

Shallow, elongated recesses 35 and 36 (Figs. 5 and 6), having arcuate end walls, open on opposite sides of the body 16 into the bottom of the recesses 19 and 2% that, together with the walls 13, 14 define the chambers 21 and 22, respectively. Intermeshing gear pump members 37 and 38 are accommodated in the recess 35; intermeshing gear pump members 39 and 40 are accommodated in the recess 36.

Corresponding gear pump members 37 and 39 in the respective recesses form the driving gear structures. For this purpose, these gear members 37 and 39 are aligned and carried at the opposite ends of a common shaft 41 that extends transversely of the body member 16. The other gear structures 38 and 40 are driven by the gear members 37 and 39, respectively, and have stub shafts 42 and 43 piloted in appropriate recesses of the body 16.

A cover plate 44 extends over the recess 35 and d..- fines with this recess a housing accommodating the gear members 37 and 38. Agroove 45 (see Figs. 3 and 5), extending beyond the plate 44, forms an inlet from the chamber 21 to the space between the intermeshing gear members 37 and 38. Upon rotation of the gear member.

37 in a direction indicated by the arrow 46, material is carried around the arcuate walls of the recess 35 to the opposite side of the intermeshing gears.

The passageway 25 intersects the recess 35 on that side of the intermeshing gear structures 37 and 38 opposite the inlet 45. The passageway 25 thus forms the discharge from the gear pump structures.

In a similar manner, a cover plate 47 covers the recess 36 to define a housing accommodating the gear pump members 39 and 40. A groove 48 (see Fig. 3) forms the inlet to the gear pump structure for the material of the chamber 22. The gear pump members 39 and 40 urge the material into the upwardly extending passageway 26 of the body 16 in a similar manner.

Since the gear pump structures provide definite displacement of material for one revolution, and since the gear pump structures are operated by a common shaft 41, the ratio of the constituent materials delivered to the mixing chamber is constant. In the present instance, the gear pump structures are of equal displacement, and hence the ratio of the constituent materials in the final mixture is unity. By changing the relative size of the pump structures, the ratio of the constituent materials in the final mixture is changed.

The constituent materials that are discharged through ports 25 and 26 into the mixing chamber 30 are thoroughly intermixed by the action of the chopping member 32 in the mixing chamber 30. The viscous constituents of the sealing compound are forced through the various ports and through the mixer 32 by the pressure created by the gear pumps.

The chopper member 32 is carried at the upper end of a vertical drive shaft 49. The shaft 49 extends into the body 16 from that side thereof opposite the body recess It extends axially into the mixing chamber 30 from the bottom thereof between the passages 25 and 26. The chopper member 32 has projections 50 (Figs. 3 and 4) arranged spirally generally as interrupted threads.

These projections 50 have but slight clearance with respect to the walls of the aperture 29 of the fitting 28 defining the chamber 30. Flow of material is thus made to progress through the small spaces between the projections 50. Intel-mixture of the constituent materials is thus provided.

While the projections 5%) are arranged generally helically, they may be arranged in such manner as to induce a slight reverse flow of the constituent materials. This produces a slight churning action, further aiding the intimate intermixture of the materials.

The projections 50 need not all be axially aligned so that there are abutments in the path of axial movement of the material between the projections 50. Such arrangement causes changes in direction, further aiding the mixing operation. When the materials are urged upwardly beyond the chopper 32, they are mixed to a substantially homogeneous consistency.

For operating the chopper 32 and the gear pump structures, an air motor is provided. Such air motor is ac commodated within a hollow stock portion or handle 51 (Figs. 1 and 2).

This stock portion 51 has a reduced end threadedly accommodated at the lower end of a downwardly opening recess 56 in the lower portion of the body 16. The stock portion 51 forms a grip by the aid of which the device is carried.

The shaft 49 extends within the hollow stock portion 51 and upwardly beyond the upper end thereof axially through the body recess 56 (Figs. 3 and 4). The shaft then passes through an aperture extending between the bottom of the mixing chamber 30 and the recess 56. Bearing structures 31 and 82 support the shaft 49 respectively below the aperture 80 and at the upper end of the stock portion 51.

The air motor is supplied with pressurized air from a remote source by the aid of a hose 53 (see Figs. 1 and 2) connected to the apparatus by the aid of a coupling 52. The flow of air to the air motor is controlled by a valve that is operated by a lever 54.

A worm 55 extends in the lower recess 56 of the body 16 and is appropriately fastened to the shaft 49 (Figs. 3 and 4). This worm 55 operates the shaft 41 for the gear pump structures 37-40. For this purpose, a worm wheel 57 is mounted intermediate the gear pump shaft 41 for imparting rotation thereto. This worm wheel 57 is accommodated in a substantially circular recess 83 between the opposed halves 16a, 16b of the body 16 (Figs. 4 and 6) and adjoining the recess 56 for the worm 55. The wheel 57 is driven by the worm 55 so that power is taken from the shaft 49 to operate the gear pump structures.

Substantial heat may be generated by the helical chopping member 32. In order to cool the material and retard setting, provisions are made for utilizing the air discharged by the air motor.

An annular space 84 (Figs. 3 and 4), provided between the base of the reduced. upper end of the stock portion 51 and the body 16, receives the cooled air discharged within the hollow stock portion 51 by the air motor. For this purpose, a plurality of radial ports 59 are provided that extend between the space 84 and the hollow interior of the stock portion 51.

A passageway 58 of the body 16 establishes communication between the annular space 84 and an annular chamber 60 surrounding the flange 31 of the mixing chamber fitting 28.

A plurality of substantially equiangularly spaced ports 61 extend longitudinally upwardly of the fitting 28 from the chamber 60. These ports at their upper ends discharge to the ambient atmosphere.

Restrictions 62 at the lower ends of the ports 61 ensure uniform distribution of air to all ports 61, and thus uniform cooling about the mixing chamber 30. The 'air passing through the ports 61 conducts heat from the fitting 28 and maintains cool operation in the mixing chamber 30.

Pressurized air from any appropriate source and entering the stock portion through the fitting 52 is also used a'rssge s for applying pressure to the exterior of the flexible walls 13 and 14 to initiate the flow of the material. Air from the source via the flexible hose 53 and the coupling 52 is passed to the space between the flexible wall-s 13 and 14 and the casing members 11 and 12.

For this purpose, a conduit 63, communicating with the source of pressurized air, is provided (Figs. 1, 2 and 4). A coupling 64 (see Fig. 4) is threadedly accommodated in a recess 65 of the body 16. This recess 65 is intersected on opposite sides by passageways 66 and 67 of the body 16 (Fig. 7). These passageways '66 and 67 open in the ends of the flanges 17 and .18, and thus between the flexible walls 13 and 14 and the casing members 11 and 12 joined to the inside and the outside of the flanges 17 and 18 respectively. The application of pressure to the exterior of walls 13 and 14 initiates the flow of the constituent materials of the chambers 21 and 22.

The inside surfaces of the casing members 11 and :12 are scored, as at 68 and 69. This scoring ensures that the pressurized air can act over a substantial area of the flexible walls 13 and 14, and that the flexible walls 13 and 14 do not accidentally seal the discharge ends of the apertures 66 and 67.

Substantially circular screens 70 and 71 have terminal edges engaged by edges of the walls 13 and 14 secured by the rings 23 and 24. These screens 70 and 71 prevent the walls 13 and 14 from overlying the grooves 45 and 48, forming the inlet to the gear pumps. It is thereby ensured that substantially the entire contents of the chambers 21 and 22 may readily be supplied to the gear pump structures without interference.

The flow of air through the conduit 63 is controlled simultaneously with the air motor and by the lever 54. This is accomplished by coupling the air connection 63 (Figs. 1 and 2) to the interior of stock '51 between the air control valve and the air port 65. Accordingly, upon operation of the operator 54, the air motor causes operation of the chopper 32 and the gear pump structures, and pressurized air is also communicated to the interior of the casing structures 11 and 12 for initiating flow of material by collapsing the walls 13 and 14.

As shown most clearly in Fig. 8, the chambers 21 and 22 can be filled With constituent materials by the aid of separate exteriorly opening passageways 72 and 73. These passageways 72 and 73 open at their inner ends in the chambers 21 and 22 respectively (see, also, Fig. 2).

Removable plugs 74 and 75 close the exterior openings of the passageways 72 and 73. Material can be inserted into the chambers 21 and 22 via the apertures 72 and 73 without disturbing any of the other structure of the apparatus, since air pressure means alone is used forcing the walls 13 and 14 toward the body structure 16.

In the form of the invention shown in Figs. 9 to 12,

the structure is supported on a base 90. It is intended primarily for preparing relatively large quantities of the mixture, to be stored in air-tight receptacles for a limited time.

A mechanism 91 (Fig. 10) is provided for intimately mixing the constituent materials.

A rotatable shaft 92 is mounted in a standard 93 fixed to the base 90. The right-hand end of the shaft projects beyond the standard 93 and carries a chopper member 94 similar to the chopper member 32, as in the previous form.

An annular bracket 95 has an axial recess 96 that receives the chopper 94 and the shaft end 92. The bracket 95 has a flange 97 abutting the annular surface of the standard 93 surrounding the shaft 92. Bolts 98, passing through the flange 97 and engaging the standard 93, secure the bracket 95 to the standard 93.

The recess 96 of the bracket 95 defines a mixing chamber through which constituent materials pass. For feeding the constituent materials to the mixing chamber, the standard 93 has a pair of passageways or ports 99 and .fi 100 (Fig. 12 each opening at one end laterally of the standard, and at the other end into an annular space 101. This annular space 101 is formed in the recess 96 between the right-hand end surface of the standard 93 about the shaft and the bottom of the chopper 94 that is spaced therefrom.

Material enters the mixing chamber via the standard passageways 99 and 100 by the aid of conduits 102 and 103 that are connected to the standard at the lateral open ings of the passageways 99 and 100 by the aid of couplings 104.

The materialpasses through the chamber and past the chopper 94 through a fitting 105 carried at the end of the bracket 95. The fitting 105 establishes communication between a flexible hose 106 and an aperture .107 in the bottom of the bracket recess .96. The flexible hose 1% is used to fill appropriate'storage receptacles, such as cans.

The manner in which the constituent materials are passed to the conduits 102 and 103 is shown most clearly in Fig. 11. A hopper 108, mounted on a body 109, in turn carried by the base 90, is adapted to serve as a reservoir for one of the constituent materials.

In the present instance, the hopper 108 is substantially cylindrical so that it may receive tin or can 110 in which the material may be supplied. The can 110 may be an ordinary paint can, in which the constituent is usually stored. When it is desired to use the mixer, the bottom of the can is cut away, the cover is removed, and the full can is then inverted and placed in hopper 108. The bottom of the can may be left in place to ensure uniform downward flow of the contents. The hopper 108 has an inner annular shoulder 111 forming a stop cooperating with the usual annular edge of the can or receptacle 110.

A gear pump structure operates to urge the material from the bottom portion 112 of the hopper into the conduit 103. For this purpose, the upper surface of the body 109, in communication with the interior of the hopper 108, has a recess 113 in which gear pump members 114 and 115 are closely accommodated. These pump members 114 and 115 project upwardly of the upper surface of the body 109 through an appropriate slot and into the lower portion 112 of the hopper 108.

Upon rotation of the gear pump members 114 and 115 in the direction of the arrows 116, the material of the hopper 112 is urged about the arcuate end walls of the recess 113 and to the lower portion of the recess between the intermeshing gear pump members 114 and 115.

A port 117 communicates with the bottom of the recess 113 and forms the discharge of the gear pump. This port 117 is in communication with the conduit 103 by the aid of a coupling 118.

The gear pump members 114 and 115, being at the bottom of the hopper, are by gravity continuously supplied with the material as long as such material is present. The gear pump structures 114 and 115 positively urge the material through the conduit 103 and into the mixing chamber provided by the bracket 95 via the passageway 100.

In an entirely analogous manner, a hopper 119 and a gear pump structure in cooperation therewith urge the other constituent material through the conduit 102, through the passageway 99 of the standard 93, and into the mixing chamber provided by the bracket 95.

For operating the gear pump structures and for rotating the chopper 94, an air motor 120, mounted upon the base 90, is provided. The air motor 120 operates take'oif shafts 121 and 122 for the gear pump structures by the aid of a transmission mechanism 123 mounted centrally of the base 90. The transmission mechanism 123 thus operates the shafts 92.

As in the previous form, the gear pump structures for the respective constituents, operated by a common trans- 7 mission mechanism 123, control the relative proportion of the constituent materials in the final mixture.

As in the previous form, provisions are made for utilizing the air discharged from the air motor 120 for cooling the bracket 95 forming the mixing chamber. For this purpose, a conduit 124 establishes communication between the exhaust of the air motor 120 and a plurality of ports 125 of the bracket 95 (Fig. 10) that extend parallel to the axis of the mixer.

These through ports 125 surround the mixing sham ber formed by the bracket aperture 96. The ports 125 open at one end in an annular recess 126 provided in the flange 97 of the bracket.

This annular space 126 communicates with the conduit 124 by the aid of a coupling 127 and a passageway 128 in the standard 93. This passageway 128 opens in the end surface of the standard 93 over which the flange 97 and its recess 126 extend. I

The other ends of the longitudinally extending ports 125 discharge to the ambient atmosphere. Restrictions at the inlets to the ports 125, as at 129, may be provided for ensuring uniform distribution of air to all ports 125.

When tin or can 110 is substantially emptied, it may be removed, still leaving a residue of material in the lower portion 112 of the hopper 108 beneath the can. A full can can be quickly inserted into the hopper 108 or 119 without requiring shut-down of the apparatus.

The inventor claims:

1. In a mixer structure: a mixer body having inlet openings at opposite sides of the body and having a separate outlet opening; flexible walls defining with the body, a pair of chambers for the reception respectively of the constituents to be mixed; said inlet openings communicating with said chambers; and means for simultaneously applying fluid pressure to the exterior of the walls.

2. In a mixer structure: a body having walls forming a pair of separate spaces; flexible members for each space, each of said flexible members having portions secured to one wall of the respective spaces to define chambers with said one wall; said body having means forming a mixing recess and having a pair of passages, each passage opening at opposite ends in said recess and the respective chambers; said mixing recess having an outlet; and means for simultaneously conducting fluid under pressure into said spaces exteriorly of said flexible members.

3. In a mixer structure: a body having walls forming a pair of separate spaces; flexible members for each space, each of said flexible members having portions secured to one wall of the respective spaces to define chambers with said one wall; said body having means forming a mixing recess and having a pair of passages, each passage opening at opposite ends in said recess and the respective chambers; means for simultaneously conducting fluid under pressure into said spaces exteriorly of said flexible members; and means carried by the body for limiting movement of said flexible members toward the end openings of corresponding passages.

4. In a mixer structure: a body having walls forming a pair of separate spaces; flexible members for each space, each of said flexible members having portions secured to one wall of the respective spaces to define chambers with said one wall; said body having means forming a mixing recess and having a pair of passages, each passage opening at opposite ends in said recess and the respective chambers; means for simultaneously conducting fluid under pressure into said spaces exteriorly of said flexible members; and pump structures cooperating with the passages urging material from said chambers to said mixing recess.

5. In a mixer structure: a body having exterior annular flanges on opposite sides of the body, said body having means forming a mixing chamber; said body having passages extending between the recess and the exterior surfaces of the body within the respective flanges; a pair of substantially hemispherical flexible walls having 8 edges secured within the respective flanges; a pair of substantially hemispherical casing members secured exteriorly of said flanges respectively for defining pressure chambers about said flexible walls; and means for simultaneously conducting fluid under pressure to said pressure chambers.

6. In a mixer structure: a body having exterior annular flanges on opposite sides of the body, said body having means forming a mixing chamber; said body having passages extending between the recess and the exterior surfaces of the body within the respective flanges; a pair of substantially hemispherical flexible walls having edges secured within the respective flanges; and a pair of substantially hemispherical casing members secured exteriorly of said flanges respectively for defining pres sure chambers about said flexible walls; said body having ports opening in the end surfaces of said flanges for simultaneously conducting fluid under pressure to said pressure chambers.

7. In a mixer structure: a body having exterior annular flanges on opposite sides of the body, said body having means forming a mixing chamber; said body having passages extending between the recess and the exterior surfaces of the body within the respective flanges; a pair of substantially hemispherical flexible walls having edges secured within the respective flanges; a pair of substantially hemispherical casing members secured exteriorly of said flanges respectively for defining pressure chambers about said flexible walls; and screens between said body surfaces and said flexible walls; said body having ports opening in the end surfaces of said flanges for simultaneously conducting fluid under pressure to said chambers.

8. In a mixer structure: a body having exterior annular flanges on opposite sides of the body, said body having means forming a mixing chamber; said body having passages extending between the recess and the exterior surfaces of the body within the respective flanges; a pair of substantially hemispherical flexible walls having edges secured within the respective flanges; a pair of substantially hemispherical casing members secured exteriorly of said flanges respectively for defining pressure chambers about said flexible walls; said casing members having grooves extending on the inner surfaces of said members arcuately substantially from the edges of said members; and means for simultaneously conducting fluid under pressure to said pressure chambers.

9. In a mixer structure: a body having a means forming a mixing chamber and a plurality of exteriorly opening ports arranged about said mixing chamber that are separated from said mixing chamber; a rotary mixer in the chamber; a pair of passage means forming inlets to the chamber and opening in surfaces of the body; a pair of flexible walls defining spaces in communication respectively with the passage means; means forming pressure chambers about said flexible walls; an air motor for rotating the mixer; means for conducting the exhaust air of said motor to said ports; and means for simultaneously conducting fluid pressure to said pressure chambers.

10. In a mixer structure: a body having a pair of exterior surfaces; a pair of flexible walls having edges in sealing relationship with the surfaces respectively to form supply chambers for constituent materials to be mixed; means forming a mixing chamber between the surfaces; passage means establishing communication between each surface of the body and the recess; means forming a pair of pressure chambers about the flexible walls; and means for simultaneously conducting fluid under pressure to the pressure chambers.

11. In a mixer structure: a body having a pair of exterior surfaces; a pair of flexible walls having edges in sealing relationship with the surfaces respectively to form supply chambers for constituent materials to be mixed; screens interposed between the surfaces and the flexible walls; means forming a mixing chamber between the surfaces; passage means establishing communication between each surface of the body and the recess; means forming a pair of pressure chambers about the flexible walls; and means for simultaneously conducting fluid under pressure to the pressure chambers.

12. In a mixer structure: a body having means forming a mixing chamber, said body also having a pair of exterior surfaces on opposite sides of the body; said body having means defining spaces at the surfaces respectively, in each of which a pair of intermeshing gear structures may be mounted; a pair of intermeshing gear structures in each of said spaces and forming with the Walls of its corresponding space a gear pump; means forming a pair of passages establishing communication between said mixing chamber and the outlet of said pumps; and means cooperating with said surfaces for containing material and supplying material to the inlets to the pumps; a rotary mixer in the mixing chamber; and common means for operating the pumps and the mixer.

13. In a mixer structure: a body having opposite side surfaces that are substantially parallel to each other, said body having means forming a mixing chamber between the surfaces; there being an elongate recess in each surface; a gear pump structure in each recess, each including first and second intermeshing gear members; a common shaft extending across the body and mounting the first gear members of each structure at opposite ends; means secured to the body at the surfaces over said recesses to enclose the structures; a rotary mixer in said mixing chamber; means for rotating said mixer and said shaft; means forming passages from the mixing chamber to the outlets respectively of the gear pump structures; and means cooperating with said surfaces to define spaces for constituent materials, and in communication with the inlets to the pumps respectively.

14. In a mixer structure: a body having opposite side surfaces that are substantially parallel to each other, said body having means forming a mixing chamber between the surfaces; a rotary mixer in the chamber; a shaft mounting said mixer and extending within the body heneath the mixing chamber; said surfaces of said body each having recesses; a gear pump structure in each recess, and each including a driving gear member; a shaft extending transversely of the body and mounting said members at opposite ends; wall means cooperating with the surfaces to define spaces for constituent materials; and passage forming means from each space to the inlet of its corresponding pump structure; passage forming means from each pump structure to said mixing chamber; means operatively connecting said shafts; and means for rotating said shafts.

15. In a mixer structure: a body having a mixing chamber at one end, said body having opposite side surfaces; a rotary mixer member in the chamber; means cooperating with the surfaces and carried by the body to define spaces for constituent materials; passage forming means from the spaces to said mixing chamber; means forming a plurality of exteriorly opening ports spaced about said mixing chamber; a hollow stock carried by the body; an air motor carried in said stock for rotating the mixer member, said air motor discharging within the upper portion of the hollow stock; and passage forming means establishing communication between the upper portion of said stock and said ports.

16. In a mixer structure: a body having an outwardly opening annular recess; a fitting threadedly accommodated in said recess and having a recess opposed to and aligned with said body recess, the end of said fitting having an annular surface extending about the end of said fitting recess and engaging the bottom of said body surface, and forming with said body recess an annular space, said fitting having a plurality of longitudinally extending ports spaced about said fitting recess, each port leading from said annular space exteriorly of the body and fitting; a rotary mixer in the fitting recess; a rotary member carried by the body and extending into said recess and carrying said mixer; passage forming means provided on the body to form inlets within said annular surface of said fitting; and means for conducting a cooling fluid to said annular space.

17. In a mixer structure: a body having an exteriorly exposed surface; a member detachably secured to the body and having a through aperture, said aperture and a portion of the said body surface forming a mixing chamber; said body having a pair of inlet passages opening in said portion of said body surface; said member having a plurality of ports spaced about said aperture and each opening exteriorly at one end; means forming an annular space communicating with the other corresponding ends of said ports, said annular space extending about and out of communication with said chamber; a mixer in the chamber; and means for conducting a cooling fluid to said annular space.

References Cited in the file of this patent UNITED STATES PATENTS 555,451 Jonsson Feb. 25, 1896 992,581 Noonan et al. May 16, 1911 1,531,922 Graham Mar. 21, 1925 1,905,811 Culver Apr. 25, 1933 2,015,056 Barnes Sept. 24, 1935 2,077,228 De Bethune Apr. 13, 1937 2,148,608 De Stubner Feb. 28, 1939 2,189,146 Little Feb. 6, 1940 2,203,980 Burt June 11, 1940 2,307,566 Browne Jan. 5, 1943 2,572,049 Oakes Oct. 23, 1951 

